"My mother's body had no heart."

Kikumitsu Genma is a cheerful, if slightly spaced out, high school girl, recently orphaned after the death of her mother. After moving in with some relatives, she picks up a part-time job at a local cafe with her schoolmate.

Kikumitsu is also a "second generation" demon, capable of taking a knife to the face with no issue and able to rip off your head without a moment's thought.

She's working to save up money so she can finally visit her absent her father. But who - or what, more accurately - is he...?

PS "Nisei" ("second generation") is a term used to refer to ethnically Japanese people born outside of Japan. Kikumitsu is a Nisei because she is ethnically demonic but born outside of the demon world.